Ulansuhai Formation

Ulansuhai Formation Stratigraphic range: Turonian
Type	Geological formation
Unit of	Dashuigou Group
Location
Region	Inner Mongolia
Country	China

The Ulansuhai Formation (simplified Chinese: 乌梁素海组; traditional Chinese: 烏梁素海組; pinyin: Wūliángsùhǎi Zǔ) is a geological formation in Inner Mongolia, north China. Dinosaur remains are among the fossils that have been recovered from the formation.

The Ulansuhai Formation has traditionally been considered to date to the Aptian-Albian stages of the Late Cretaceous, due to similarities between the Ulansuhai fauna and known Aptian formations. However, radiometric dating done on underlying formations has shown this to be incorrect. Due to the age of underlying rocks, the Ulansuhai Formation cannot be older than the Turonian stage of the Late Cretaceous, about 92 Ma.

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